1. Field of the Invention
This invention relates to an IC memory card and more particularly, to an IC memory card having a structure which increases in the capacity thereof.
2. Description of the Related Art
A super-thin IC package, a TCP (tape carrier package), is a package which has been developed recently to provide an IC memory card having a large capacity. This package has achieved a thickness about half the thickness of an IC package called a TSOP (thin small outline package). The use of TCP enables four ICs to be stacked on top of one another in a thickness of 3.3 mm which is the standard thickness of the IC memory card specified by Japan Electronic Industry Association.
FIGS. 11 and 12 are respectively schematic plan and side elevational views illustrating a conventional IC memory card which employs TCP. In these figures, ICs which employ TCP, e.g., memory ICs 2, are mounted on the two surfaces of a substrate 1. A connector 3 is connected to the side portion of the substrate 1 for electrically connecting the memory ICs to an external circuit.
The IC memory card arranged in the manner described above suffers from the following problems. That is, (1) since the substrates 1 are laid on top of one another in two stages, the connector 3 has complicated form and structure. (2) Soldering of the connector 3 to the substrates 1 is difficult. (3) Since the substrates 1 in the upper and lower stages are separated from each other, they are susceptible to noises. (4) Mixed mounting of conventional IC packages called TSOP and TCPs is impossible.